The present disclosure relates broadly to a system and method for harvesting rainwater. In one exemplary implementation, the disclosure comprises a do-it-yourself rainwater harvesting system for homeowners which utilizes a downspout diverter and an aesthetically desirable rain barrel. Rainwater harvesting is the gathering, or accumulating and storing, of rainwater. Traditionally, rainwater harvesting has been practiced in areas where water exists in plenty, and has provided drinking water, domestic water, water for livestock, water for irrigation and a way to increase ground water levels.